Running a bead all the way around a 3in slip-on flange looks like the toughest part of this job to me, since the joint circles a pipe made of cylindrical steel with no corners to reset at. The maker handles it with a steady dipping rhythm: the rod goes into the molten puddle with a weaving motion, and the finished bead comes out uniform, holding a consistent woven pattern around the whole joint.
The setup deserves a close look. The torch carries a ceramic cup and a tungsten electrode, running a number 8 cup, with the amperage set at 210amps. Filler is 1/8th rod. In my view that combination seems well matched to a joint of this size, though I would be curious how the same settings behave on thinner stock.
The TIG torch strikes an electric arc for the weld, and a side-by-side comparison of the weld is included. To my eye that comparison makes the evenness of the bead easy to judge. For recording, a green welding lens filter was used, and the view stays readable through the brightest moments of the arc.
One thing is left open: the specific metal alloy, the filler material and the torch model are not stated anywhere. Those particulars would matter a lot to anyone planning a similar joint. I hope they turn up eventually, because the rest of the recipe is laid out clearly enough to follow.
Project by Scott Raabe. Watch it on their YouTube channel: